/*
 * Oreka -- A media capture and retrieval platform
 *
 * Copyright (C) 2005, orecx LLC
 *
 * http://www.orecx.com
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License.
 * Please refer to http://www.gnu.org/copyleft/gpl.html
 *
 */
#pragma warning( disable: 4786 ) // disables truncated symbols in browse-info warning

#define _WINSOCKAPI_		// prevents the inclusion of winsock.h

#include "G722Codec.h"
#include <cstring>
G722ToPcmFilter::G722ToPcmFilter()
{
	// Initialize decoder
	memset(&m_ctx, 0, sizeof(m_ctx));
	g722_decode_init(&m_ctx, 64000, G722_SAMPLE_RATE_8000);
}

G722ToPcmFilter::~G722ToPcmFilter()
{
	memset(&m_ctx, 0, sizeof(m_ctx));
}

FilterRef G722ToPcmFilter::Instanciate()
{
	FilterRef Filter(new G722ToPcmFilter());
	return Filter;
}

void G722ToPcmFilter::AudioChunkIn(AudioChunkRef& inputAudioChunk)
{
	int in_samples = 0;
	int out_samples = 0;
	short pcmdata[8000];
	CStdString logMsg;

	memset(pcmdata, 0, sizeof(pcmdata));
	m_outputAudioChunk.reset();

	if(inputAudioChunk.get() == NULL) {
		return;
	}

	if(inputAudioChunk->GetNumSamples() == 0) {
		return;
	}

	AudioChunkDetails outputDetails = *inputAudioChunk->GetDetails();
	if(SupportsInputRtpPayloadType(outputDetails.m_rtpPayloadType) == false)
	{
		return;
	}

	in_samples = inputAudioChunk->GetNumSamples();
	unsigned char* inputBuffer = (unsigned char*)inputAudioChunk->m_pBuffer;

	out_samples = g722_decode(&m_ctx, pcmdata, inputBuffer, in_samples);

	m_outputAudioChunk.reset(new AudioChunk());
	outputDetails.m_rtpPayloadType = -1;
	outputDetails.m_encoding = PcmAudio;

	outputDetails.m_numBytes = (out_samples * 2);
	short* outputBuffer = (short*)m_outputAudioChunk->CreateBuffer(outputDetails);

	memcpy(outputBuffer, pcmdata, out_samples*2);
}

void G722ToPcmFilter::AudioChunkOut(AudioChunkRef& chunk)
{
	chunk = m_outputAudioChunk;
}

AudioEncodingEnum G722ToPcmFilter::GetInputAudioEncoding()
{
	return G722Audio;
}

AudioEncodingEnum G722ToPcmFilter::GetOutputAudioEncoding()
{
	return PcmAudio;
}

CStdString G722ToPcmFilter::GetName()
{
	return "G722ToPcm";
}

bool G722ToPcmFilter::SupportsInputRtpPayloadType(int rtpPayloadType)
{
	return rtpPayloadType == 9;
}

void G722ToPcmFilter::CaptureEventIn(CaptureEventRef& event)
{
	;
}

void G722ToPcmFilter::CaptureEventOut(CaptureEventRef& event)
{
	;
}

//=====================================================================

/*
 * SpanDSP - a series of DSP components for telephony
 *
 * g722_decode.c - The ITU G.722 codec, decode part.
 *
 * Written by Steve Underwood <steveu@coppice.org>
 *
 * Copyright (C) 2005 Steve Underwood
 *
 *  Despite my general liking of the GPL, I place my own contributions
 *  to this code in the public domain for the benefit of all mankind -
 *  even the slimy ones who might try to proprietize my work and use it
 *  to my detriment.
 *
 * Based in part on a single channel G.722 codec which is:
 *
 * Copyright (c) CMU 1993
 * Computer Science, Speech Group
 * Chengxiang Lu and Alex Hauptmann
 *
 * $Id: g722_decode.c 48661 2006-12-21 00:08:21Z mattf $
 */

/*! \file */

#include <stdio.h>
#ifndef WIN32
#include <inttypes.h>
#endif
#include <memory.h>
#include <stdlib.h>
#if 0
#include <tgmath.h>
#endif

#if !defined(FALSE)
#define FALSE 0
#endif
#if !defined(TRUE)
#define TRUE (!FALSE)
#endif

#ifdef WIN32
static inline int16_t saturate(int32_t amp)
#else
static __inline__ int16_t saturate(int32_t amp)
#endif
{
    int16_t amp16;

    /* Hopefully this is optimised for the common case - not clipping */
    amp16 = (int16_t) amp;
    if (amp == amp16)
	return amp16;
    if (amp > INT16_MAX)
	return	INT16_MAX;
    return  INT16_MIN;
}
/*- End of function --------------------------------------------------------*/

static void block4(g722_decode_state_t *s, int band, int d);

static void block4(g722_decode_state_t *s, int band, int d)
{
    int wd1;
    int wd2;
    int wd3;
    int i;

    /* Block 4, RECONS */
    s->band[band].d[0] = d;
    s->band[band].r[0] = saturate(s->band[band].s + d);

    /* Block 4, PARREC */
    s->band[band].p[0] = saturate(s->band[band].sz + d);

    /* Block 4, UPPOL2 */
    for (i = 0;	 i < 3;	 i++)
	s->band[band].sg[i] = s->band[band].p[i] >> 15;
    wd1 = saturate(s->band[band].a[1] << 2);

    wd2 = (s->band[band].sg[0] == s->band[band].sg[1])	?  -wd1	 :  wd1;
    if (wd2 > 32767)
	wd2 = 32767;
    wd3 = (s->band[band].sg[0] == s->band[band].sg[2])	?  128	:  -128;
    wd3 += (wd2 >> 7);
    wd3 += (s->band[band].a[2]*32512) >> 15;
    if (wd3 > 12288)
	wd3 = 12288;
    else if (wd3 < -12288)
	wd3 = -12288;
    s->band[band].ap[2] = wd3;

    /* Block 4, UPPOL1 */
    s->band[band].sg[0] = s->band[band].p[0] >> 15;
    s->band[band].sg[1] = s->band[band].p[1] >> 15;
    wd1 = (s->band[band].sg[0] == s->band[band].sg[1])	?  192	:  -192;
    wd2 = (s->band[band].a[1]*32640) >> 15;

    s->band[band].ap[1] = saturate(wd1 + wd2);
    wd3 = saturate(15360 - s->band[band].ap[2]);
    if (s->band[band].ap[1] > wd3)
	s->band[band].ap[1] = wd3;
    else if (s->band[band].ap[1] < -wd3)
	s->band[band].ap[1] = -wd3;

    /* Block 4, UPZERO */
    wd1 = (d == 0)  ?  0  :  128;
    s->band[band].sg[0] = d >> 15;
    for (i = 1;	 i < 7;	 i++)
    {
	s->band[band].sg[i] = s->band[band].d[i] >> 15;
	wd2 = (s->band[band].sg[i] == s->band[band].sg[0])  ?  wd1  :  -wd1;
	wd3 = (s->band[band].b[i]*32640) >> 15;
	s->band[band].bp[i] = saturate(wd2 + wd3);
    }

    /* Block 4, DELAYA */
    for (i = 6;	 i > 0;	 i--)
    {
	s->band[band].d[i] = s->band[band].d[i - 1];
	s->band[band].b[i] = s->band[band].bp[i];
    }

    for (i = 2;	 i > 0;	 i--)
    {
	s->band[band].r[i] = s->band[band].r[i - 1];
	s->band[band].p[i] = s->band[band].p[i - 1];
	s->band[band].a[i] = s->band[band].ap[i];
    }

    /* Block 4, FILTEP */
    wd1 = saturate(s->band[band].r[1] + s->band[band].r[1]);
    wd1 = (s->band[band].a[1]*wd1) >> 15;
    wd2 = saturate(s->band[band].r[2] + s->band[band].r[2]);
    wd2 = (s->band[band].a[2]*wd2) >> 15;
    s->band[band].sp = saturate(wd1 + wd2);

    /* Block 4, FILTEZ */
    s->band[band].sz = 0;
    for (i = 6;	 i > 0;	 i--)
    {
	wd1 = saturate(s->band[band].d[i] + s->band[band].d[i]);
	s->band[band].sz += (s->band[band].b[i]*wd1) >> 15;
    }
    s->band[band].sz = saturate(s->band[band].sz);

    /* Block 4, PREDIC */
    s->band[band].s = saturate(s->band[band].sp + s->band[band].sz);
}
/*- End of function --------------------------------------------------------*/

g722_decode_state_t *g722_decode_init(g722_decode_state_t *s, int rate, int options)
{
    if (s == NULL)
    {
	if ((s = (g722_decode_state_t *) malloc(sizeof(*s))) == NULL)
	    return NULL;
    }
    memset(s, 0, sizeof(*s));
    if (rate == 48000)
	s->bits_per_sample = 6;
    else if (rate == 56000)
	s->bits_per_sample = 7;
    else
	s->bits_per_sample = 8;
    if ((options & G722_SAMPLE_RATE_8000))
	s->eight_k = TRUE;
    if ((options & G722_PACKED)	 &&  s->bits_per_sample != 8)
	s->packed = TRUE;
    else
	s->packed = FALSE;
    s->band[0].det = 32;
    s->band[1].det = 8;
    return s;
}
/*- End of function --------------------------------------------------------*/

int g722_decode_release(g722_decode_state_t *s)
{
    free(s);
    return 0;
}
/*- End of function --------------------------------------------------------*/

int g722_decode(g722_decode_state_t *s, int16_t amp[], const uint8_t g722_data[], int len)
{
    static const int wl[8] = {-60, -30, 58, 172, 334, 538, 1198, 3042 };
    static const int rl42[16] = {0, 7, 6, 5, 4, 3, 2, 1, 7, 6, 5, 4, 3,	 2, 1, 0 };
    static const int ilb[32] =
    {
	2048, 2093, 2139, 2186, 2233, 2282, 2332,
	2383, 2435, 2489, 2543, 2599, 2656, 2714,
	2774, 2834, 2896, 2960, 3025, 3091, 3158,
	3228, 3298, 3371, 3444, 3520, 3597, 3676,
	3756, 3838, 3922, 4008
    };
    static const int wh[3] = {0, -214, 798};
    static const int rh2[4] = {2, 1, 2, 1};
    static const int qm2[4] = {-7408, -1616,  7408,   1616};
    static const int qm4[16] =
    {
	      0, -20456, -12896,  -8968,
	  -6288,  -4240,  -2584,  -1200,
	  20456,  12896,   8968,   6288,
	   4240,   2584,   1200,      0
    };
    static const int qm5[32] =
    {
	   -280,   -280, -23352, -17560,
	 -14120, -11664,  -9752,  -8184,
	  -6864,  -5712,  -4696,  -3784,
	  -2960,  -2208,  -1520,   -880,
	  23352,  17560,  14120,  11664,
	   9752,   8184,   6864,   5712,
	   4696,   3784,   2960,   2208,
	   1520,    880,    280,   -280
    };
    static const int qm6[64] =
    {
	   -136,   -136,   -136,   -136,
	 -24808, -21904, -19008, -16704,
	 -14984, -13512, -12280, -11192,
	 -10232,  -9360,  -8576,  -7856,
	  -7192,  -6576,  -6000,  -5456,
	  -4944,  -4464,  -4008,  -3576,
	  -3168,  -2776,  -2400,  -2032,
	  -1688,  -1360,  -1040,   -728,
	  24808,  21904,  19008,  16704,
	  14984,  13512,  12280,  11192,
	  10232,   9360,   8576,   7856,
	   7192,   6576,   6000,   5456,
	   4944,   4464,   4008,   3576,
	   3168,   2776,   2400,   2032,
	   1688,   1360,   1040,    728,
	    432,    136,   -432,   -136
    };
    static const int qmf_coeffs[12] =
    {
	   3,  -11,   12,   32, -210,  951, 3876, -805,	 362, -156,   53,  -11,
    };

    int dlowt;
    int rlow;
    int ihigh;
    int dhigh;
    int rhigh;
    int xout1;
    int xout2;
    int wd1;
    int wd2;
    int wd3;
    int code;
    int outlen;
    int i;
    int j;

    outlen = 0;
    rhigh = 0;
    for (j = 0;	 j < len;  )
    {
	if (s->packed)
	{
	    /* Unpack the code bits */
	    if (s->in_bits < s->bits_per_sample)
	    {
		s->in_buffer |= (g722_data[j++] << s->in_bits);
		s->in_bits += 8;
	    }
	    code = s->in_buffer & ((1 << s->bits_per_sample) - 1);
	    s->in_buffer >>= s->bits_per_sample;
	    s->in_bits -= s->bits_per_sample;
	}
	else
	{
	    code = g722_data[j++];
	}

	switch (s->bits_per_sample)
	{
	default:
	case 8:
	    wd1 = code & 0x3F;
	    ihigh = (code >> 6) & 0x03;
	    wd2 = qm6[wd1];
	    wd1 >>= 2;
	    break;
	case 7:
	    wd1 = code & 0x1F;
	    ihigh = (code >> 5) & 0x03;
	    wd2 = qm5[wd1];
	    wd1 >>= 1;
	    break;
	case 6:
	    wd1 = code & 0x0F;
	    ihigh = (code >> 4) & 0x03;
	    wd2 = qm4[wd1];
	    break;
	}
	/* Block 5L, LOW BAND INVQBL */
	wd2 = (s->band[0].det*wd2) >> 15;
	/* Block 5L, RECONS */
	rlow = s->band[0].s + wd2;
	/* Block 6L, LIMIT */
	if (rlow > 16383)
	    rlow = 16383;
	else if (rlow < -16384)
	    rlow = -16384;

	/* Block 2L, INVQAL */
	wd2 = qm4[wd1];
	dlowt = (s->band[0].det*wd2) >> 15;

	/* Block 3L, LOGSCL */
	wd2 = rl42[wd1];
	wd1 = (s->band[0].nb*127) >> 7;
	wd1 += wl[wd2];
	if (wd1 < 0)
	    wd1 = 0;
	else if (wd1 > 18432)
	    wd1 = 18432;
	s->band[0].nb = wd1;

	/* Block 3L, SCALEL */
	wd1 = (s->band[0].nb >> 6) & 31;
	wd2 = 8 - (s->band[0].nb >> 11);
	wd3 = (wd2 < 0)	 ?  (ilb[wd1] << -wd2)	:  (ilb[wd1] >> wd2);
	s->band[0].det = wd3 << 2;

	block4(s, 0, dlowt);

	if (!s->eight_k)
	{
	    /* Block 2H, INVQAH */
	    wd2 = qm2[ihigh];
	    dhigh = (s->band[1].det*wd2) >> 15;
	    /* Block 5H, RECONS */
	    rhigh = dhigh + s->band[1].s;
	    /* Block 6H, LIMIT */
	    if (rhigh > 16383)
		rhigh = 16383;
	    else if (rhigh < -16384)
		rhigh = -16384;

	    /* Block 2H, INVQAH */
	    wd2 = rh2[ihigh];
	    wd1 = (s->band[1].nb*127) >> 7;
	    wd1 += wh[wd2];
	    if (wd1 < 0)
		wd1 = 0;
	    else if (wd1 > 22528)
		wd1 = 22528;
	    s->band[1].nb = wd1;

	    /* Block 3H, SCALEH */
	    wd1 = (s->band[1].nb >> 6) & 31;
	    wd2 = 10 - (s->band[1].nb >> 11);
	    wd3 = (wd2 < 0)  ?	(ilb[wd1] << -wd2)  :  (ilb[wd1] >> wd2);
	    s->band[1].det = wd3 << 2;

	    block4(s, 1, dhigh);
	}

	if (s->itu_test_mode)
	{
	    amp[outlen++] = (int16_t) (rlow << 1);
	    amp[outlen++] = (int16_t) (rhigh << 1);
	}
	else
	{
	    if (s->eight_k)
	    {
		amp[outlen++] = (int16_t) rlow;
	    }
	    else
	    {
		/* Apply the receive QMF */
		for (i = 0;  i < 22;  i++)
		    s->x[i] = s->x[i + 2];
		s->x[22] = rlow + rhigh;
		s->x[23] = rlow - rhigh;

		xout1 = 0;
		xout2 = 0;
		for (i = 0;  i < 12;  i++)
		{
		    xout2 += s->x[2*i]*qmf_coeffs[i];
		    xout1 += s->x[2*i + 1]*qmf_coeffs[11 - i];
		}
		amp[outlen++] = (int16_t) (xout1 >> 12);
		amp[outlen++] = (int16_t) (xout2 >> 12);
	    }
	}
    }
    return outlen;
}
/*- End of function --------------------------------------------------------*/
/*- End of file ------------------------------------------------------------*/
